Tea making device having an improved liquid collection chamber

ABSTRACT

A device for making tea, which device comprises a brewing chamber ( 2 ) for enclosing a tea-pad, means for supplying heated water through one or more openings in the upper wall of the brewing chamber, and a restricted opening ( 8 ) in the lower wall ( 1 ) of the brewing chamber ( 2 ), so that tea is squirted into a liquid collection chamber ( 10 ) underneath the brewing chamber ( 2 ). The lower wall ( 11 ) of the liquid collection chamber ( 10 ) is provided with a substantial circular ridge ( 14 ) around the location where the tea hits the lower wall ( 11 ) of the liquid collection chamber ( 10 ).

The invention is related to a device for making tea, whereby the devicecomprises a brewing chamber for enclosing a tea-pad, means for supplyingheated water through one or more openings in the upper wall of thebrewing chamber, and one or more restricted openings in the lower wallof the brewing chamber, so that tea is squirted into a liquid collectionchamber underneath the brewing chamber.

Such device is described in WO-A-2005/016092. The described devicecomprises a water reservoir and means for heating the water and pumpingit to the holes in the upper wall of the brewing chamber, so that theheated water can enter the brewing chamber under pressure. The brewingchamber can be filled with a tea-pad containing pieces of tea leafs. Theheated water will pass through the tea-pad, so that tea is extracted.After the extraction process, the brewed tea leaves the brewing chamberthrough a restricted opening in the lower wall (the bottom) of thebrewing chamber, whereby it is squirted against the lower wall (thebottom) of the liquid collection chamber, which liquid collectionchamber is located underneath the brewing chamber. From the liquidcollection chamber, the tea is further guided to a tea outflow memberfor filling one or two cups standing near the device. The portion of thedevice comprising the upper wall of the brewing chamber can hingeupwardly with respect to the stationary part of the device comprisingthe brewing chamber and the liquid collection chamber, so that thebrewing chamber can be opened and a new tea-pad can be inserted in thebrewing chamber for the next extraction process.

In order to achieve an optimal extraction process, the heated water hasto stay for a certain time in the brewing chamber, and therefore theoutflow opening in the lower wall of the brewing chamber has a relativesmall dimension, so that the outflow of the tea is restricted. Suchrestricted opening causes a liquid jet, so that the tea squirts againstthe bottom of the liquid collection chamber. After hitting that bottom,the tea is spread out over the lower wall of the liquid collectionchamber, whereby air inclusions (air bubbles) in the tea are initiated,resulting in some foam, or even a layer of foam on the brewed tea.

However, foam in the brewed tea has to be limited or, if possible, hasto be avoided, because foam decreases the quality of the tea. Althoughsome foam on the upper surface of the tea does not affect the taste ofthe tea, in general, the presence of foam is not appreciated by teadrinking persons. In case the same device is also used for makingcoffee, the creation of foam is a positive effect of the brewingprocess, because foam increases the quality of the brewed coffee.

An object of the invention is a device for making tea comprising abrewing chamber for enclosing a tea-pad, whereby the tea is flowing fromthe brewing chamber to the liquid collection chamber through arestricted opening in the lower wall of the brewing chamber, whereby thecreation of foam is reduced.

Another object of the invention is to reduce the quantity of residualtea in the liquid collection chamber after the tea is brewed. Thereby,the merging of fresh brewed tea with residual tea from a former brewingprocess is reduced. Furthermore, the presence of residual tea requiresmore frequent rinsing and/or cleaning of the liquid collection chamber.

To accomplish with one or both of these objects, the lower wall of theliquid collection chamber is provided with a substantial circular ridgearound the location where the tea hits the lower wall of the liquidcollection chamber. After the tea hits the lower wall of the liquidcollection chamber, the tea is spread out over the lower wall, wherebythe speed of the liquid flow decreases during its motion over that lowerwall. It has been found out that heavy turbulence arises in the liquidflow when the flow hits the side wall of the liquid collection chamber.It has appeared that said turbulence causes the creation of foam in thetea. Furthermore, it has been found that such creation of foam can bereduced by introducing an obstacle like a ridge on the lower wall of theliquid collection chamber, whereby the liquid flow passes over the ridgebefore it hits the side wall of the liquid collection chamber.Therefore, a circular ridge on the bottom of the liquid collectionchamber reduces effectively the creation of foam in the tea in aneffective way.

In a preferred embodiment, the diameter of the substantial circularridge is between 25 mm and 60 mm, and preferably between 35 mm and 50mm. Of course, the optimal diameter of the substantial circular ridgedepends from the speed of the liquid that is spreading out over thelower wall of the liquid collection chamber, but a diameter as mentionedabove has given satisfying results.

Preferably, the height of the substantial circular ridge is between 0.05mm and 5 mm, and more preferably between 1.5 mm and 4 mm. A relativesmall height has already a foam reducing effect on the liquid flow, buta height between 1.5 mm and 4 mm reduces the creation of foamconsiderably.

In a preferred embodiment, the lower wall of the liquid collectionchamber has a raised portion at the location where the tea hits saidlower wall, so that the tea is flowing over a slope downwards to thesubstantial circular ridge. By experimentation it has been found outthat the presence of such slope at the bottom of the liquid collectionchamber further reduces the creation of foam in the tea. The slope mayextend over a major part of the lower wall of the liquid collectionchamber or may extend only over a smaller part, for example an annularportion, of said lower wall. Preferable, the slope has an angle between1° and 20° with respect to the horizontal plane, more preferable anangle between 3° and 10°.

In order to make sure that all tea can leave the space that issurrounded by the substantial circular ridge, in a preferred embodiment,the substantial circular ridge has an interruption forming apass-through for liquid. Most of the tea will pass the substantialcircular ridge by flowing over the ridge, but after the tea supply tothe liquid collection chamber is finished, the last quantity of tea canleave the area surrounded by the ridge through said pass-through in saidcircular ridge.

Preferably, the lower wall of the liquid collection chamber issubstantially positioned in an inclined plane, whereby the substantialcircular ridge is present on the inclined lower wall of the liquidcollection chamber. Thereby, the interruption of the substantialcircular ridge is located at the lowest part of said ridge.

It has been found that foam can also be created by liquid drops fallingon the radial directed liquid flow over the bottom of the liquidcollection chamber. Therefore, in a preferred embodiment, means arepresent for reducing liquid drops falling down in the area within thesubstantial circular ridge from the upper wall of the liquid collectionchamber. The presence of such means can be regarded as a separateinvention aiming at reducing foam in the tea, which invention can beapplied in combination with, but also in absence of, said substantialcircular ridge.

In a preferred embodiment, said means for reducing liquid drops fallingdown is a layer of porous material on at least the central part of theupper wall of the liquid collection chamber. The porous material willabsorb the liquid (water) that may condense on it, so that there is noliquid that may form drops at the surface of the upper wall of theliquid collection chamber where the layer of porous material is present.

Preferably, at least the central part of the surface of the upper wallof the liquid collection chamber is inclined, so that drops of condensedliquid will not fall down, but will slide along the surface of the upperwall of the liquid collection chamber downwardly. Thereby the liquid canbe guided to a location where it can fall down without causing foam, orto the side wall of the liquid collection chamber in order to furtherslide down along said side wall. In a preferred embodiment, at least amain part of the surface of the upper wall of the liquid collectionchamber has a substantial conical shape, so that the upper wall issloping down towards the side wall of the liquid collection chamber. Theinclination of the central part of the upper wall of the liquidcollection chamber is preferably at least 1° and more preferably between3° and 10°.

In a preferred embodiment, the lower wall of the liquid collectionchamber is substantially positioned in an inclined plane, so that thelowest portion of said lower wall is at a location at the edge of saidlower wall, whereby said lowest portion is provided with an oblongoutflow opening along said edge, whereby a guiding surface abuts on saidoblong outflow opening for guiding the tea downwardly towards a teaoutflow member. By guiding the tea to the tea outflow member, thecreation of foam is avoided. In case the tea would be guided through atube, the tube may remain filled with tea after the tea stops flowing,because of the capillary action of the tube. By making use of a guidingsurface, there is no remaining tea and furthermore there is no creationof foam in the tea.

The tea guiding surface instead of a tea guiding tube can be applied incombination with said substantial circular ridge and/or said means forreducing liquid drops falling down from the upper wall of the liquidcollection chamber, but it can also be applied separately, so that itcan be considered as a separate invention.

In a preferred embodiment, the guiding surface abuts on the lower edgeof the side wall of the liquid collection chamber, which edge is alsothe edge of the oblong outflow opening. Thereby, the tea flowsautomatically against said guiding surface when it leaves the lower wallof the liquid collection chamber, so that it can be further guided indownward direction.

Preferably, the lower wall of the liquid collection chamber is providedwith a channel for guiding liquid in the direction of an outflow openingat the edge of the lower wall, so that the quantity of residual liquidafter the brewing process is reduced.

The invention is furthermore related to a removable part of the deviceas described above, which removable part comprises the lower wall of thebrewing chamber and the liquid collection chamber. The removable partmay also comprise the tea outflow member. The part can be removed inorder to rinse it or to clean it, for example in a dish-washer.

The invention will now be further elucidated by means of a descriptionof a part of the tea making device, which part comprises the lower wallof the brewing chamber and the complete liquid collection chamber.Thereby, reference is made to the drawing comprising three sectionalviews of said part of the tea making device, in which:

FIG. 1 is a sectional view indicated with arrows I in FIGS. 2 and 3;

FIG. 2 is a sectional view indicated with arrows TI in FIGS. 1 and 3:and

FIG. 3 is a sectional view indicated with arrows III in FIGS. 1 and 2.

The figures are only diagrammatic representations, whereby only partsthat are relevant for the elucidation of the invention are indicated.

FIGS. 1 and 2 show the lower wall 1 of the brewing chamber 2, whichlower wall 1 is made by deforming a metal plate. The circular edge 3 ofthe lower wall 1 can abut against the substantial flat lower surface ofthe upper wall (not shown) of the brewing chamber 2, which upper wallcan be hinged away in order to replace the tea-pad (not shown) that canbe present in the brewing chamber 2. Said upper wall of the brewingchamber 2 is provided with a number of openings in order to supplyheated water to the brewing chamber 2, which water can pass through thetea-pad, whereby tea is extracted.

The lower part of wall 1 is covered with a disc-like drainage member 4,which drainage member 4 is provided with channels 5 (grooves orrecesses) at its upper surface. The drainage member 4 is made of plasticmaterial and the channels 5 are positioned in radial direction. FIG. 1shows one channel 5 and other channels 5 are indicated with stripedlines 6 in FIGS. 1 and 2. The extracted tea can leave the tea-padthrough these channels 5. The upper surface of drainage member 4 can beprovided with other recesses, for example the recesses between verticalcylindrical protrusions. The brewed tea can flow from the tea-padthrough these recesses 5 to the central recess 7 and can leave thebrewing chamber 2 through the restricted opening 8. Restricted opening 8is present in a member 9 of plastic material, which member 9 is attachedto the lower side of the lower wall 1 of the brewing chamber 2.

As shown in FIGS. 1 and 2, a liquid collection chamber 10 is presentunderneath the brewing chamber 2. The lower wall 11 of the liquidcollection chamber has a central horizontal portion 12, which portion 12is raised with respect to the surrounding part of the lower wall 11.Around the raised portion 12 is an annular inclined portion 13 of thelower wall 11. Further away from the central horizontal portion 12 is acircular ridge 14. The lower wall 11 is inclined, as is shown in FIG. 2,except for the central horizontal portion 12. In the lower portion ofthe circular ridge 14 is an interruption 15, where liquid can flow tothe lowest portion of the lower wall 11. In that lowest portion of thelower wall 11 is an oblong opening 16 forming an outflow opening for thebrewed tea.

The liquid collection chamber 10 has a substantial cylindrical side wall17. The upper part of side wall 17 is attached to member 9. The sidewall 17 of the liquid collection chamber 10 has an extended portion 18in downward direction at the location of the oblong outflow opening 16,which extended portion 18 forms a vertical guiding surface 19 for thetea flowing through the oblong outflow opening 16.

The tea is flowing from the brewing chamber 2 through the restrictedopening 8 and is squirting against the central horizontal portion 12 ofthe lower wall 11 of the liquid collection chamber 10. Then, the tea isflowing in radial outward direction over the upper surface of the lowerwall 11. It passes the inclined portion 13 and subsequently flows overthe circular ridge 14. The presence of the ridge avoids the creation offoam when the tea reaches the side wall 17 of the liquid collectionchamber 10. Subsequently, the tea is flowing to the lowest portion ofthe lower wall 11 and leaves the liquid collection chamber 10 throughthe oblong outflow opening 16. The tea is guided by the vertical guidingsurface 19 to a tea outflow member (not shown) for filling one or twocups standing near the device.

The liquid in the liquid collection chamber 10 is warm, and thereforewater may condense on the walls of the liquid collection chamber 10. Incase water condenses on the upper wall of the liquid collection chamber10, water drops may fall down, and it has found that such drops causefoam in the tea when the drops fall into the flow of tea in the centralportion 12,13 of the lower wall 11. Therefore, the central portion ofthe lower side of member 9 has a conical-shaped concave surface 20, sothat water drops do not fall from that central portion, but will slidealong the conical-shaped surface to a location further away from thecentral portion 12,13 of the lower wall 11, in the shown embodiment evenoutside the circular ridge 14.

In order to further improve the outflow of residual liquid from theliquid collection chamber, upper surface of the lower wall 11 isprovided with a channel or groove 21 to guide the liquid towards theoblong outflow opening 16.

The embodiment of the device for making tea as described above is onlyan example, many other embodiments are possible.

The invention claimed is:
 1. A device for making tea comprising: abrewing chamber for enclosing a tea-pad, means for supplying heatedwater through one or more openings in the upper wall of the brewingchamber, and a restricted opening in the lower wall of the brewingchamber, so that tea is squirted into a liquid collection chamberunderneath the brewing chamber, wherein the lower wall of the liquidcollection chamber is provided with a substantial circular ridge aroundthe location where the tea hits the lower wall of the liquid collectionchamber between the location where the tea hits the lower wall of theliquid collection chamber and a wall enclosing the liquid collectionchamber.
 2. A device as claimed in claim 1, wherein the diameter of thesubstantial circular ridge between 25 mm and 60 mm.
 3. A device asclaimed in claim 1, wherein the height of the substantial circular ridgeis between 0.05 mm and 5 mm.
 4. A device as claimed in claim 1, whereinthe lower wall of the liquid collection chamber has a raised portion atthe location where the tea hits said lower wall, so that the tea isflowing over a slope downwards to the substantial circular ridge.
 5. Adevice as claimed in claim 1, wherein the substantial circular ridge hasan interruption in order to form a pass-through for liquid.
 6. A deviceas claimed in claim 1, further comprising: means for reducing liquiddrops falling from at least a part of the upper wall of the liquidcollection chamber.
 7. A device as claimed in claim 6, wherein at leastthe central part of the upper wall of the liquid collection chamber isprovided with a layer of porous material.
 8. A device as claimed inclaim 1, wherein at least the central part of the surface of the upperwall of the liquid collection chamber is inclined.
 9. A device asclaimed in claim 8, wherein at least a main part of the surface of theupper wall of the liquid collection chamber has a substantial conicalshape.
 10. A device as claimed in claim 1, wherein the lower wall of theliquid collection chamber is substantially positioned in an inclinedplane, so that the lowest portion of said lower wall is at a location atthe edge of said lower wall whereby said lowest portion is provided withan oblong outflow opening along said edge, whereby a guiding surfaceabuts on said oblong outflow opening for guiding the tea downwardlytowards a tea outflow member.
 11. A device as claimed in claim 10,wherein the guiding surface abuts on the lower edge of the side wall ofthe liquid collection chamber, which edge is also the edge of the oblongoutflow opening.
 12. A device as claimed in claim 1, wherein the lowerwall of the liquid collection chamber is provided with a channel forguiding liquid in the direction of an outflow opening at the edge of thelower wall.
 13. A removable part of the device according to claim 1,comprising the lower wall of the brewing chamber and the liquidcollection chamber.
 14. A device as claimed in claim 1, wherein thediameter of the substantial circular ridge is between 35 mm and 50 mm.15. A device as claimed in claim 1, wherein the height of thesubstantial circular ridge is between 1.5 mm and 4 mm.